[Asus Padfone X and S] xdaernie:
THE CONCERN:

Padfone S - LTE signal icon in status bar absent and LTE option in settings absent. Just H, H+, and 4G icon.

MY QUESTION:

Has anyone ran into this same senario and fixed it? Or, come up with a real concrete understading of the LTE bands on PFS WW firmware?

POST ABBREVIATIONS:

PFS=Padfone S (International) model.

PFX=Padfone X (AT&T) model.

H=HSPA=3G

H+=HSPA+= 4G

4G= 4G posibly LTE (That I am trying to figure out.)

WHAT I DID:

So, did a full system wipe and flashed the most recent official Asus PFS firmware on an (AT&T) PFX model with TWRP 3.0

THE OUTCOME OF CHANGING FIRMWARE SO FAR:

Overall, phone works incredibly well. Smooth. No bugs except for LTE band issue. However, I don't know if it's an actual issue.

Flashing to PFS gave me Android 5.0, but most importantly the Padfone Station works perfectly as well Google Play store without having to modify anything. (Both reasons I didn't keep CM12 or CM13.)

THE CONCERN AGAIN:

Concern is that in this PFS firmware, LTE signal icon in status bar absent and LTE option in settings absent. Just H, H+, and 4G icon

WHAT MY PHONE DOES:

Only displays H, H+, and 4G in status bar next to signal strength.

In Settings > Cellular Networks section, only gives me Preferred Network Type option of 2G, 3G, 2G 3G 4G.

No LTE option. Yet, phone specs indicates that it has the bands.

LTE bearer option in APN does nothing.

WHAT I DID:

Downloaded an app called LTE DISCOVERY (Google Play Store), and it shows that when signal status shows 4G icon, it actually is using the LTE band 2. (See Photos below)

BAND 1900 Mhz band 2= LTE

However, it doesn't stay on a 4G Band 2 frequency that long. Usually jumps back to H and H+. And data connection disconnects constantly. I have to disable and re-enable data to get it to reconnect.

Note: My area has a strong AT&T LTE signal, and on PFX firmware LTE worked great. I know the hardware is capable of connecting to network. Just not available on PFS firmware, I guess?

WHAT I MIGHT DO NEXT:

I am considering trying to flash modem image from Padfone X, but am hesitant.

Also considering using an app called Nexus 4 LTE Modem Flasher (Google Play Store) which flashes preloaded LTE bands and helps enable the, but I'm hesitant to use it since this is not a Nexus.

Also considering flashing Official Asus Padfone INFINITY WW firmware to see if that is any different. Infinity also has a Padfone Station.

Has anyone ran into this same senario and fixed it? Let me know please.

My Phone:

Phone model: Was ASUS T00D (PFX)...flashed to official ASUS_T00N

ASUS PadFone S Firmware: V12.2.2.43 Only for WW SKU

Micro SIM CARD: Straight Talk (AT&T LTE Version)

Boot Img: TWRP 3.0

Bootloader: Unlocked

Rooted: Yes, Rooted by KingRoot

Busybox: Yes

APN settings: Correct for SIM and network.

PFS V.S. PFX NETWORK STANDARD COMPARISON. (Noticing that Padfone S firmware is missing key LTE bands 1700MHz AWS( 4 )/850MHz( 5 )/700MHz( 17 ), . Look below.)

PADFONE S NETWORK STANDARD

WCDMA/TDD-LTE

Data Rate:*

DC-HSPA+: UL 5.76 / DL 42 Mbps

LTE :UL 50 / DL 150 Mbps*

2G :

EDGE/GSM :*

850MHz/900MHz/1800MHz/1900MHz*

3G :

WCDMA :

900MHz( 8 )/1900MHz/2100MHz

4G :

FDD-LTE: (TW/APAC version)

2100MHz( 1 )/1900MHz( 2 )/1800MHz( 3 )/2600MHz( 7 )/900MHz( 8 )/700MHz( 28 )

FDD-LTE: (EU version)*

2100MHz( 1 )/1900MHz( 2 )/1800MHz( 3 )/2600MHz( 7 )/900MHz( 8 )/800MHz( 20 )

PADFONE X NETWORK STANDARD

Network Standard

3G :

850MHz/900MHz/1900MHz/2100MHz

4G :

LTE Bands: (US version)

2100MHz(1)/1900MHz(2)/1800MHz(3)/1700MHz AWS(4)/850MHz(5)/2600MHz(7)/700MHz(17)

That being said, my hardware is capable, but the PFS firmware I flashed is not going to access those frequencies and bands.

Soooo, going to have to flash modems for them somehow.

Anyone successful in this arena of flashing modem to include LTE band 4,5 and 17 on PFS?